Cutting mechanism release for mowers



April 1950 s. E. HlLB LOM 2,504,686

CUTTING MECHANISM REILEASE FOR IOWERS Original Filed Oct. 1a, 1943 v 1Fl6.3 50 4o IN VEN TOR.

Samue/ E. Hi/b/om Patented Apr. 18, 1950 CUTTING MECHANISM RELEASE FORMOWERS I Samuel E. Hilblom, Chicago, 111., assignor to InternationalHarvester Company, a corporation of New Jersey Original applicationOctober 18, 1943, Serial No. 506,661. Divided and this application June20, 1947, Serial No. 755,946

14 Claims.

The invention relates to a mower, and more particularly to a mower ofthe type in which a supporting frame carries cutting mechanism forrelease in response to the striking of an obstruction by the latter.

Mowers of the type generally referred to are conventional in the respectthat the mower structure includes a carrying or supporting frame onwhich the cutting mechanism is carried for movement with respect to thecarrying frame in a. direction opposite to that in which the mowerstructure is traveling. In some instances, the cutting mechanism ispivoted to the carrying frame for such rearward swinging movement abouta vertical axis; in other instances, the rearward movement of thecutting mechanism with respect to the supporting frame may betranslatory. Various types of release mechanisms have been provided formaintaining the normal or operating position of the cutting mechanismwith respect to the supporting frame, these mechanisms being releasablein response to excessive force applied to the cutting mechanism upon thestriking of an obstruction. Several problems arise in the constructionand use of such mechanisms. One of the principal problems is involved inproviding a release mechanism that is simplein construction, inoperation, and not likely to require constant attention. Another problemis to provide a release mechanism that is automatically restorable toits initial position when the cutting mechanism is returned to itsnormal position after the obstruction has been eliminated.

The invention contemplates and has for an important object the provisionof an improved release mechanism overcoming the disadvantages ofprevious devices and incorporating the features of simple and fool-proofconstruction and automatic restoration. Another object of the inventionis to provide a release mechanism comprising relatively few parts,preferably in the form of a pair of members connected together forrelative movement and normally lockable by yieldable locking meanscontrollable by the cutting mechanism as it swings or moves fromoperating position to release position and is returned to operatingposition. Another object of the invention is to provide the releasabledevice in such manner that it may be readily attached to conventionalmowers. v

The foregoing and other important objects and desirable features of theinvention will appear in greater detail in the following description ofa preferred embodiment of the invention, taken in conjunction with theaccompanying sheet of drawings, in which:

Fig. 1 is a plan view of the rear portion of a mower of one type inwhich the invention may be utilized;

Fig. 2 is an enlarged side view of a portion of the release mechanism byitself, the view illustrating the parts of the mechanism in normalposition; i r

Fig. 3 is a view similar to that appearing in Figd. 2, but with theparts in released position; an

Fig. 4 is an end elevational view of the structure shown in Fig. 2, theview being taken substantially in the direction of the arrow 4 on Fig.2.

Although the following description will proceed with respect to theinvention as utilized in a tractor mounted mower, it should beunderstood that the invention may be similarly used in mowers of othertypes. The exact details of construction forming the basis of thepresent disclosure should not be taken as limiting the application oftheinvention. r

Only the rear portion of the tractor on which the mower is mounted isshown in the drawings. The tractor includes a mainframe I0 carried on apair of rear traction wheels H and a transverse axle structure II. Thecarrying or supporting frame for the mower is indicated generally by thenumeral [3 and comprises a pair of rearwardly extending supportingmembers I4 connected at their rear ends by a transverse frame member IS.The structure oi? the mower frame forms no part of the presentinvention. The details thereof are disclosed and claimed in myco-pending application Serial No. 747,037, filed May 9, 1947.

The left-hand or stubbleward end of the frame l3 carries rigidly thereona supporting bracket I5 on which is mounted a second bracket [6. Theconnection between the brackets I5 and I6 may be formed by a verticalpivot member 11. The bracket I6 includes a longitudinal sleeve I8 inwhich is carried the forwardly bent end of a transversely extendingcoupling bar 19. The coupling bar forms part of the cutting mechanismframe to be presently described. The'connection between the coupling bar19 to the sleeve l8 of the bracket 16 is on a longitudinal horizontalaxis so that the coupling bar may have vertical movement with respect tothe supporting frame 13. The cutting mechanism frame is completed by ayoke 20 connected to the right-hand end of the 3 7 coupling bar andcutting mechanism including a cutter bar 2| and knife 22. The cutter bar2| may be connected to the yoke 20 in the conventional manner.

The cutting mechanism is driven ,by a transverse pitman 23, connected atits grassward end to the knife 22 and at its stubbleward end to aneccentric 24 carried on a shaft 25 driven by a belt 26 on a pulley 21.The pulley 21 is in turn carried by a shaft 28 which is journaled in ahearing 29 associated with the bracket IS. The shaft 28 is driven by atelescopic drive shaft 30 connected to a power take-off shaft 3| of thetractor. The drive for the cutting mechanism may be generallyconventional and forms no detailed part o the present invention.

Tlie raising and lowering of the cutting mechanism with respect to thecoupling bar I9 is ac- 46 fits into the recess 33. Each of the lugs 46is provided with a beveled edge 46. The, lug 46 that fits in the recess31 ha its beveled edge 46 complementary to the beveled edge 4| of thatrecess, and the beveled edge of the other lug is complementary to thebeveled edge 42 of the recess 38 (Fig. 4). Although the structuraldetails of only one end of the member 44 are visible in Fig. 4, itshould be understood that the opposite ends are symmetrical toaccomplish the association with the recesses 31 and 33 as describedabove.

The release mechanism includes yieldable Imeans. preferably'in the formof a coiled compression spring 41, interposed between the outer face ofthe arm 43 and a washer 43 secured tothe shaft 39 by a nut 49. Thefunction of the sprin 41 is to maintain the member 44 in releasablycomplished through a rock shaft 32 on the frame l3 and. connectionsbetween that rock shaft and a second rock shaft 33 on the cuttingmechanism frame. The latter rock shaft is connectedby suitable linkage,indicated generally at 34, with the cutter bar 2|. may be of anysuitable type, one form of which This construction likewise isillustrated in greater detail in my co-pending application, SerialNumber 506,661, now Patent 7 No. 2,454,697 issued November 23, 1948identified above.

The normal operating position of the cutting mechanism frame is thatshown in solid lines in Fig. 1. The pivot l1 betweenthe supporting framel3 and coupling bar I! permits the cutting mechanism to swing to theposition shown in broken lines in Fig. 1 upon the encountering of anobstruction. The cutting mechanism is maintained in its operatingposition and is releasable for movement to its released position bymeans to be described below. i

The supporting frame l3 includes at the grassward side thereof a supportindicated generally by the numeral 35. The support includes a disc orplate'36 provided with a pair of substantially diametrically opposedrecesses 31 and 38 (Figs. 2 and 3), both of which open radiallyoutwardly with respect to the center of the plate 36. The plate 36includes, preferably integrally therewith, a laterally grasswardlyextending shaft 'or stud 39. The recess 31 is bordered at one edgethereof by an outstanding lug 40 rigidly secured to or formed as a partof the plate 36. The opposite edge of the recess 31 is provided with anlocked position against the plate 36 so that the cam elements onthe twoparts are engaged.

The plate 36 further includes a stop member in the form of 9. lug 66rigidly secured to the outer face of the plate. The arm 43 may beconnected, as by a link 6|, to the yoke 26 of the cutting mechanismframe. The link is of course rigid, .atleast in the directioncorresponding to movement of the cutting mechanism frame with respect tothe supporting frame, the purpose of which'will be presently described.a I,

In the operation of a mowerequipped with the releasable device hereinset forth, the cutting the arm 43 in a clockwise direction (as viewed inits marginal edge that extends substantially diametrically in line'withthe beveled edge 4| of the recess 31 is provided with a beveled orinclined surface 42. The portions thusdescribed provide cam elementsthatare cooperatively engageable with cam elements on a second portionof therelease mechanism that will be described below.

The second portion of the mechanism preferably takes the form of anjarm43 carried by theshaft 39 for angular movement relative to the-- plate36. The arm carries rigidly thereon a cross member 44 which normallylies diametrically across the plate 36 in such a manner that 'it iscoincident generally with the diameter of the plate passing through therecessesor notches .31

and 38 (Fig. 2) Each of the -diametrically op:

posite ends of the member 44 is provided with a cam lug 45. when theparts are in the positions shown in Fig. 2, the lug 46 at one end of themember engages the recess 31, and the other lug Figs. 2 and 3) the link6| thus being placed under tension. The compression on the spring 41will be overcome if the force is or, suflicient magnitude and thesurfaces 46 on the lugs 46 of the member 44 will camover the camsurfaces 4| and 42 of the recesses 31 and 33 respectively as the member44 and arm 43 move both'angularly and axially on the shaft 33 withrespect to the plate 36.

The cutting mechanism frame will then swing to the position shown inbroken lines in Fig. -1. The lug 45 that normally engages the recess 33will now have moved angularlyabout the axis of the shaft 39 to aposition where further angular movement thereof is interrupted by thestop 66 on the plate '36. The engagement of the arm 44 with the stop 50prevents further movement of the arm and, because of the link 6|,further rearward movement of the cutting mechanism is prevented.

The tractor may be reconnected to the cutting mechanism frame by'meansof moving the tractor rearwardly with respect to the cutting mechanismof the cutting mechanism forwardly with respect to the tractor, dueregard being had to'th elimji nation of the obstruction that causedrearward swinging of the cutter bar. In either event, relative movementbetween the supporting frame 13 and cutting'mechanismframe for thenurpose'of restoring the cutting mechanism to operating position alsoeiiects restoration of the releasable device to its initial position.Since the link 6| is rigid and is connected between the yoke "and arm43, return movement of the cutter bar will effect counter-clockwiseangular movement of the lug on the other in the-art. It shouldbeunderstood, of course.

that the present embodiment of the invention is subject to numerousmodifications and alterations,

'means-for connecting the other all of which may be made withoutdeparting from the spirit and scope of the appended claims.

What is claimed is:

1. For a mower having a supporting frame and a cutting mechanism framecarried by the supporting frame for movement relative to the supportingframe from an operating position to a released position upon thestriking of an obstruction: means for holding the cutting mechanismframe in operating position and releasable to provide for the movementof the cutting mechanism frame to the aforesaid released position,comprising a stationary cam plate on one frame; a movable cam plateassociated with the stationary plate for angular and axial movementrelative thereto; means providing cooperating cam forced rearwardly uponthe encountering of an obstruction thereby.

2. Releasablemeans for a'mower as set forth inclaim 1, in which: thecooperating cam elements include a recess in one cam plate and a camplate normally engaging the recess.

3. Releasable meansfor a mower as set forth in claim 2, in which: thecam-plate having the recess includes a stop element engageable by thelug on the other cam plate after predetermined relative angular movementof the cam plates,

4. Releasable means for a' mower as set forth in claim 1, in which: themeans connecting the crank arm to the said other mounting member isrigid in the direction of return movement of the cutting mechanism fromreleased position to operating. position so that such return movement ofthe cutting mechanism acts to restore the in claim 1, in which: the axisof relative angular movement of the cam plates is normal to thedirection of travel of the mower; and one cam plate is in the form of adisk on which its interengageable cam element is disposed radially.

6. For a mower having a supporting frame and a cutting mechanism framecarried by the supporting frame for movement relative to the supportingframe from an operating position to a released position upon thestriking of an obstruction: means for holding the cutting mechanismframe in operating position and releasable to provide for the movementof the cutting mechanism frame to the aforesaid released position,

6 member to. the cutting mechanism, said means including a crank armassociated with said other member.

7. For a mower having a supporting frame and a cutting mechanism framecarried by the supporting frame for movement relative to the supportingframe from an operating position to a released position upon thestriking of an obstruction: means for holding the cutting mechanismframe in operating position and releasable to provide for the movementof the cutting mechanism frame to the aforesaid released position,comprising a support including a shaft on one frame extending normal tothe direction of travel of the mower; a release element carried by theshaft for angular movement relative thereto and for shifting axiallythereon; means connecting the release element to the other of saidframes, said connecting means including a crank arm; means on thesupport normally engaging the release element to prevent relativeangular movement thereof; and yieldable means also on the support toprevent axial shifting of the release element except in response toforces imparted to the release element through the aforesaid connectingmeans when the cutting mechanism frame encounters an obstruction.

8. For a mower having a supporting frame and a cutting mechanism framecarried by the supcomprising a pair of members relatively angularlyreleasable elements; means for connecting one member to the mowersupporting frame; and

porting frame for movement relative to the supporting frame from anoperating position to a released position upon the striking of 'anobstruction: means for holding the cutting mechanismframe in operatingposition and releasable to provide for the movement of the cuttingmechanism frame to the aforesaid released position, comprising a supporton one frame; an arm carried-by the support for angular and axialmovement relative thereto; means connecting the arm to the other frameand rigid at least in the direction of movement of the cutting mechanismframe from released to operating position, where- ,by the arm will bemoved angularly and axially on the support when the cutting mechanismframe moves from operating to released position and is returned tooperating position; and yieldable locking means normally preventingangular and axial movement of the arm and unlockable in response toforces transmitted through the arm and connecting means by the cuttingmechanism frame when the latter encounters an obstruction, saidyieldable locking means being restorable to normal position through thearm and the aforesaid connecting means when the' cutting mechanism frameis returned to operating position.

9. For a mower having a supporting frame and a cutting mechanismframe-carried by the supporting frame for movement relative to thesupporting frame from an operating position to a released position uponthe striking of an obstruction: means for holding the cutting mechanismframe in operating position and releasable to provide for the movementof the cutting mechanism frame to the aforesaid released position,comprising a support on one frame; an arm carried by the support forangular and axial movement relative thereto; means connecting the arm tothe other frame and rigid at least in the direction of movement of thecutting mechanism frame from released to operating position, whereby thearm will be moved on the support when the cutting mechanism frame movesfrom operating to released position and is returned to operatingposition; and a releasable locking device normally preventing movementof transmitted through the arm andconnecting means by the cutting mechanm frame when the latter encounters an obstructi 11, said releasablelocking device being restorable to normal position through the arm andthe aforesaid connecting means when the cutting mechanism frame is axialmovement on said stud. andmeans for restricting rotation and axialmovement of said arm with respect to said plate,said means coinprising'a plate having apertures and correspondreturned to operating position.j

10. For a. mower having asupporting frame and a cutting mechanism framecarried by the supporting frame for movement relative to the supportingframe from an operating position to a released position upon thestriking of an obstruction: means for holding the cutting 'mechanismframe in operating position and releasable to provide for the movementof the cutting mechanism frameto the aforesaid released position,comprising a support on one frame; an arm carried by the support forangular and axial movement relative thereto; means connecting the arm tothe other frame, wherebythe arm will be moved angularly and axially inone direction on the support when, the cutting mechanism frame movesfrom operating to released position; yieldable locking means normallypreventing angular and axial movement ofthe arm and unlockable inresponse to forces transmitted through the arm and connecting means bythe cutting mechanism frame when the latter encounters an obstruction;and means for moving the arm in the opposite direction to restore thelocking means to normal position when the cutting mechanism mowerwhereby damage of the mower is elimi-.

nated upon striking an obstruction, said yieldable latch comprising astationary plate member,

an outwardly extending stud on said plate, an

armjournaled for rotation and axial movement on said stud, and means forrestricting rotation and axial movement ofsaid arm with respect to saidplate, said means including yielding means plate member, an outwardlyextending stud on 'said plate, an arm ,journaled for rotationv and inglyshaped projections on said arm and yielding means interposed between thearm and the end of the stud.

13. In a vehicle attached mower having two parts, a yieldable latchinterposedbetween the two parts of the mower whereby damage of the moweris eliminated upon striking an obstruction, said yieldable latchcomprising a stationary plate member, an outwardlyextendingfstud on saidplate, an arm journaled', for rotation and axial movement on said stud,means for restricting rotation and axial movement of said arm withrespect to said plate, 'saidmeans comprising a plate having apertures :1and correspondingly shaped projections on" said arm, and a springinterposed between the end of the stud and the arm for tending tomaintain engagement of said projections with the plate apertures.

14. In a vehicle attached :mower having two parts, a yieldable latch"interposed-. betwe'en the two parts of the mower whereby damage of "themower is eliminated upon strikingan obstruction, said yieldable latchcomprising a stationary plate member, an outwardly extending-stud onsaid plate, an arm journaled forgotation on said stud, means forrestricting rotation of said arm with respect to said plate, said'meanscomprising a plate having apertures and correspondingly shapedprojections on said arm, aspring interposed between the end of the studand the arm for tending tomaintain engagement of said projections withthe plate-apertures, and a stop projection on said plate memberforlimiting REFERENCES CITED The following references are of record in thefile of this patent:

UNITED STATES PATENTS Number 7 Name Date 1,537,629 Street "May 12, 19252,166,942 Crumb ---Juiy 25,: 1939 2,172,561 Kruse Sept. 12, 19392,291,987 Rogers Aug. 4, 1942

